Se «How A Cochlear Implant Works by Advanced Bionics» på YouTube

Useful comparison chart

The brand-independent and informational website, Cochlear Implant Online recently posted a comparison chart of the three CI-manufacturers products.

Skjermbilde

I haven’t studied it, but at first glance it seems appropriate to anybody trying to get an overview of the CI-market. Kudos to the girls running Cochlear Implant Online !

Here is the link to the actual chart

Decoding sounds from Cochlear Implants

In this informative video you can supposedly get an idea of what kind of work my brain will have to do in order to decode those artificial electronic impulses into meaningful sounds….

I wouldn’t know, if this is accurate or even if it’s true, as I haven’t been implanted yet, but would love to get comments from my CI-blog friends on this posting!

A great what-is-Cochlear-Implant video

Here is a very good informative video from the Med El Cochlear Implant-brand based in Austria.

This video shows very good what a Cochlear Implant actually does for the hearing.
It shows how a Cochlear Implant works in terms of bringing artificial sound to the brain.

Thanks to Berose and her blog on which she made me aware of the existence of this video.

Bilateral CI research findings

I will post my findings on the issue of bilateral CI on my blog. Hopefully it helps someone else too…

I want to collect the data concerning this debate, in order to get an oversight of what the medical community discover, as well as what they are writing and thinking about this issue.

Papers found in PubMed:

Patients fitted with one (CI) versus two (CI+CI) cochlear implants, and those fitted with one implant who retain a hearing aid in the non-implanted ear (CI+HA), were compared using the speech, spatial, and qualities of hearing scale (SSQ) (Gatehouse & Noble, 2004). The CI+CI profile yielded significantly higher ability ratings than the CI profile in the spatial hearing domain, and on most aspects of other qualities of hearing (segregation, naturalness, and listening effort). A subset of patients completed the SSQ prior to implantation, and the CI+CI profile showed consistently greater improvement than the CI profile across all domains. Patients in the CI+HA group self-rated no differently from the CI group, post-implant. Measured speech perception and localization performance showed some parallels with the self-rating outcomes. Overall, a unilateral CI provided significant benefit across most hearing functions reflected in the SSQ. Bilateral implantation offered further benefit across a substantial range of those functions.
(Link to more information about this paper)

Speech perception tests were performed preoperatively before the second implantation and at 3 months postoperatively. RESULTS: Results revealed significant improvement in the second implanted ear and in the bilateral condition, despite time between implantations or length of deafness; however, age of first-side implantation was a contributing factor to second ear outcome in the pediatric population. CONCLUSION: Sequential bilateral implantation leads to significantly better speech understanding. On average, patients improved, despite length of deafness, time between implants, or age at implantation.
(Link to more information about this paper)

The average group results in this study showed significantly greater benefit on words and sentences in quiet and localization for listeners using two cochlear implants over those using only one cochlear implant. One explanation of this result might be that the same information from both sides are combined, which results in a better representation of the stimulus. A second explanation might be that CICI allow for the transfer of different neural information from two damaged peripheral auditory systems leading to different patterns of information summating centrally resulting in enhanced speech perception. A future study using similar methodology to the current one will have to be conducted to determine if listeners with two cochlear implants are able to perform better than listeners with one cochlear implant in noise.
(Link to more information about this paper)

The Let Them Hear Foundation have done their own research:

Despite many insurers’ (in the US; my comment) continued erroneous assertions to the contrary, bilateral cochlear implantation is NOT an experimental or investigational procedure, and is medically necessary.  Bilateral cochlear implantation in children has been an accepted, mainstream medical practice since 1998.  Over 3000 have been performed, including over 1600 on children.

Several studies have shown that there is a vast improvement in sound localization ability in patients with bilateral cochlear implants.  In particular, the group of subjects who received a significant amount of improvement when bilaterally implanted were those who were initially implanted at a very early age, as Andrew was.  In September 2005, an international consortium of cochlear implant specialists published an article in the widely respected journal “Acta Oto-Laryngologica” formally recommending that all children with permanent bilateral profound hearing losses receive bilateral cochlear implants.  A recent publication by industry-leading otologist Dr. Robert Peters stated that:

Provision of binaural hearing should be considered the standard of care for hearing-impaired patients whenever it can be provided without significant risks. In severe to profoundly hearing impaired individuals, this can only be provided with bilateral cochlear implantation when hearing aids are inadequate. In carefully selected candidates, the benefits derived are significant, the surgical procedures well tolerated, and negative effects infrequent in both children and adults.

A second recent paper by well-known communications disorder specialist Dr. Ruth Litovsky concluded that: Bilateral CIs can offer a combination of benefits that include better ear effects, binaural summation/redundancy effects and binaural unmasking. These effects have been illustrated in numerous patients world-wide; continued work in this field will no doubt lead to further improvements and increases in the size of each of these effects, for adults and for children.Please refer to the following publications for additional information.

Another medical benefit of bilateral cochlear implantation is that it has been shown to improve speech recognition in noisy environments.  It is expected that once that a patient’s hearing with the second cochlear implant in place is maximized, they will notice a significant improvement in understanding speech in noisy environments.  Comprehending speech amidst background noise occurs commonly in real-life situations, especially in classroom settings and learning environments, at the dinner table, or while talking in a car or on a plane.  Please refer to the following studies for more details:
read more from their conclusions here…..

Minister of Health in Norway guarantees CI-operations for 2008

This is a translated, abridged and reworked version of a Norwegian article found on HLF’s website.

Guarantees CI-operations and screening of infants.

Brustad-webby Norwegian Minister of Health, Sylvia Brustad gurantees that screening of hearing on infants and CI-operations will be carried out, regardless of the cutbacks at Rikshopitalet.

In response to MP Berit Brørby (Labour Party) the Minister of Health guarantees that the operations and screening will be carried out according to the assignments the government has given Rikshospitalet. The fate of the Otolaryngology-department at Rikshospitalet has been uncertain for some time now, and the hospital was ready to implement huge and devastating cuts to the said department in February this year. Now, however, the Norwegian Department for Health and Care and Health South-East (Rikshospitalets superior administrative body) agrees in their demands to the Rikshospitalet.

Priority on Hearing-operations

“I can ensure the representative Berit Brørby that the demands set in the assigments for Rikshopitalet stands from my side. There are also no changes in the function Rikshopitalet has in this area nationwide in regards to operating and following up on children. Health South-East has now also reassured the government that the given assignments will be prioritized independent from the demands for meeting the budget for 2008.”

“The Health department has also repeated a precision to Health South-East that the goal for 100 CI-operations for adults is per definition for new patients”, writes the Minister of Health in her response to representative Brørby.

The Minister has since the summer of 2006 said that the total number of nationwide CI-operations on new adult patients shall be escalated up to the medically and statistically founded annual estimate of 200.

The waiting time for CI-operations for adults is now between three to four years.

The Minister also wrote about the all-important screening process of infants in order to start early with children with suspected hearing damage. (not directly related to the CI-issue, but nevertheless good news for the development of creating a good medical service to all things related to hearing).

My comment:

In short this means that despite the hard times for Rikshospitalet budget-wise, the CI-operations are now guaranteed. The hospital will have to find other ways to save money than to bleed the Otolaryngology-department to near-death… Good news indeed 🙂

Making sense of the world through a cochlear implant

PET20YEAROLD_HIGH March 13, 2007 –  Scientists at University College London and Imperial College London have shown how the brain makes sense of speech in a noisy environment, such as a pub or in a crowd. The research suggests that various regions of the brain work together to make sense of what it hears, but that when the speech is completely incomprehensible, the brain appears to give up trying.

The study was intended to simulate the everyday experience of people who rely on cochlear implants, a surgically-implanted electronic device that can help provide a sense of sound to a person who is profoundly deaf or who has severe hearing problems.

Using MRI scans of the brain, the researchers identified the importance of one particular region, the angular gyrus, in decoding distorted sentences. The findings are published in the Journal of Neuroscience.

In an ordinary setting, where background noise is minimal and a person’s speech is clear, it is mainly the left and right temporal lobes that are involved in interpreting speech. However, the researchers have found that when hearing is impaired by background noise, other regions of the brain are engaged, such as the angular gyrus, the area of the brain also responsible for verbal working memory – but only when the sentence is predictable.

“In a noisy environment, when we hear speech that appears to be predictable, it seems that more regions of the brain are engaged,” explains Dr Jonas Obleser, who did the research whilst based at the Institute of Cognitive Neuroscience (ICN), UCL. “We believe this is because the brain stores the sentence in short-term memory. Here it juggles the different interpretations of what it has heard until the result fits in with the context of the conversation.”

brainxrayThe researchers hope that by understanding how the brain interprets distorted speech, they will be able to improve the experience of people with cochlear implants, which can distort speech and have a high homer-simpson-wallpaper-brain-1024level of background noise.

“The idea behind the study was to simulate the experience of having a cochlear implant, where speech can sound like a very distorted, harsh whisper,” says Professor Sophie Scott, a Wellcome Trust Senior Research Fellow at the ICN. “Further down the line, we hope to study variation in the hearing of people with implants – why is it that some people do better at understanding speech than others. We hope that this will help inform speech and hearing therapy in the future.” 

A Christmas wishlist for any CI-candidate

All these books would be nice to sift through….

Also I found that a medical journal published 6 times a year by Lippincott Williams & Wilkins, called “Ear and Hearing”. They have plenty of very interesting online articles available to subscribers, abridged if youre a guest…

Same publishing house offers The Laryngoscope.

All this is a bit expensive for me at the moment, but I will keep searching….

If any of my readers have tips for websites or publications concerning CI, please let me know, I will collect and publish everything I come across…
For the time being I will focus on what interests me spesifically;

  • simultaneous bilateral vs unilateral CI,
  • CI in adults and
  • all research data and latest scientific breakthroughs…